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Garra rufa is a small freshwater benthopelagic cyprinid, originally from Southwest Asia, which has become economically relevant during the last decade. G. rufa is a worthy element to control algae growth in aquariophilia, but it is mostly known for its use in treatments of skin problems in spa’s and clinics. It was made an attempt to reproduce G. rufa in captivity, in order to respond to an increasing marketing demand for this fish, plus to get an insight on its reproductive biology and embryonic development. Groups of 5 G. rufa were inserted in twelve aquaria of 20 l, with an internal filter, aeration and placed in a controlled temperature room at 26ºC. A net placed 1.5 cm above the bottom prevented the fish from eating their own eggs. The fishes were fed three times per day and checked for the presence of eggs. The eggs were removed, placed on separate aquaria and photographed hourly at a Leica DM2000LED compound microscope, equipped with a Leica DMC2900 camera G. rufa showed almost no sexual dimorphism, except for the presence of tubercles on the snout of males, which appeared only during the reproduction period. Males were larger than females and executed high velocity persecutions after them. In a total of 28 postures, only 17 resulted in newly born fish. This was mostly due to fungal development around the eggs that caused the embryos to degenerate. There was a hatching success of 60%. The eggs showed no adhesive properties, being deposited on the bottom. The most prominent structures of the embryos were noticeable after: 3h - tail bud; 6h - optic primordium; 10h - heart beating; 15h - pectoral fins buds. They hatched between 24 to 48h and the larvae consumed the yolk sac in 48h.

Garra rufa are widely used in skin treatments at beauty and wellness institutes. This freshwater species is native from Eurasia and has a large distribution area, including river basins in Turkey and Iran. It has a high commercial value and arouse interest among fish farmers. Even so, G. rufa methods of production are still unknown. In fact, aspects that sustain a rapid and healthy growth of these fish need to be investigated, like an adequate daily dose and feeding frequency. This work aimed to establish: 1) the optimal feed dose per day, correspondent to the amount necessary for obtaining satiation, with a commercial granulated food; and 2) the optimal frequency of feeding for intensive production of G. rufa in Aquaculture. A total of 60 fishes underwent a 3 weeks acclimation period in laboratory, distributed by 6 aquaria, containing 10 fishes with similar body weight and length. The animals were initially fed with a dose correspondent to 10% of their body weight. This dose was gradually increased until complete satiation of the fishes. An optimal dose of 0.04 g fish-1 day-1 was found. Afterwards, the same fishes went through a 1 month experimental trial to evaluate the ideal feeding frequency. Fish growth was compared between feeding 0.2 g twice per day and 0.1333 g three times per day. Variations in size (total and fork length), plus body weight were evaluated at the end of the trial. One-Way ANOVA procedures revealed that the variations in weight and in fork length were similar between treatments, but the variation in total length was significantly higher with 3 daily feeding moments (p

Sea urchins are an expensive delicacy in several regions of the world. Some species, like Paracentrotus lividus, have even been over-exploited in the wild, with relevant declines of their populations. Developing and improving aquaculture techniques, such as suitable feeding diets for their rearing, is therefore necessary. Paracentrotus lividus is preferably herbivorous, feeding mainly on macroalgae. The main objective of this study was to evaluate the influence of 3 different types of diet on the survival and growth of P. lividus: Ulva sp., Asparagopsis armata and animal feed. A total of 45 wild individuals were subjected to an acclimation period at the laboratory. For each diet, 3 replicates, each one consisting of a tank containing 5 individuals, were assembled. The study lasted 6 consecutive weeks, and regular determinations of weight and diameter of the test of each animal, were performed. At the end, the gonadal index was also estimated. Mortality in the 3 diets was not very relevant, and a high survival was therefore observed. The variations in weight were not statistically different, but for the test diameter a small increase in the individuals fed with A. armata was detected. With the animal feed, the values of both variables decreased towards the end of the study. As for the gonadal index, statistical differences between the diets were not obtained. In conclusion, P. lividus adapted easily to captivity and the macroalgae diets were the most favourable for their development. Asparagopsis armata sustained the animals’ growth, while the animal feed proved to be the less suitable diet for P. lividus juveniles. Due to their low cost and ease of harvesting, macroalgal diets may be advantageous for small scale closed systems. Such an option may also assist in the environmental management of coastal areas, since Ulva sp. is abundant in eutrophic systems and A. armata is an invasive species in Europe.

The Óbidos Lagoon is the largest shallow coastal lagoon in Portugal. Like any other brackish water system, it has been potentially exposed to different sources of contamination (e.g. livestock farming, domestic and industrial sewage). Trace metals are persistent elements present in the water and sediments in their elemental and organic/inorganic forms. In fact, Cadmium is extremely pollutant due to its great solubility in water and high toxicity for organisms. Also, it is classified as a priority substance according to the European Union Water Frame directive. In this context, a seasonal environmental monitoring program was implemented in the intertidal water margins of the Óbidos Lagoon to assess the presence of Cadmium. In 2009 and 2010, eight sampling stations (S) distributed on the shores of the Óbidos Lagoon were chosen and water and sediments were seasonally collected. In all samples, cadmium concentrations were analyzed by Atomic Absorption Spectrometry, with Graphite Furnace Technique. Cadmium dissolved in the water samples was only detected during summer months, with the highest values in the Barrosa’s arm (S3: 0.35 mg/l) in 2009, and at the station further downstream (S1: 0.19 mg/l) in 2010. In the suspended fraction of the water samples the trace metal was detectable in all seasons, with the maximum concentration at the Barrosa’s arm (S4: 1.04 mg/l) in the winter of 2010. Cadmium was not detectable in the sediments during the summers and was sporadically present in the autumn and in the winter of 2009. The highest concentration in the sediments was observed at the Barrosa´s arm (S4: 140.78 mg/kg) in the spring of 2010. As a whole, cadmium contamination appears to be mostly focused on the inner areas of the lagoon, at the Barrosa´s arm, but a clear seasonal pattern of variation was not detectable. These results allow a better understanding of the environmental quality of this ecosystem and may assist in the definition of coastal management measures specifically targeted to trace metal contamination and pollution monitoring.

The gonads of sea urchins have increased interest for human consumption, as a culinary delicacy worldwide. In Europe, the species Paracentrotus lividus was identified as an ideal candidate to meet the growing demand for this product, due to its high gonadosomatic index and easy access. However, the current commercial model, based on the exploitation its natural populations, may be unsustainable. Therefore, its production in aquaculture would be beneficial to avoid depletion of natural stocks of these organisms. The present study sought to develop a culture system for Paracentrotus lividus in aquaculture, which would allow maintaining the early embryonic and larval stages of this animal. A trial was set using 3 gametal release methods (due to stress induced by capture and by injecting 0.125M and 0.250M of potassium chloride) and 3 densities of sea urchin embryos (530 embryos/L, 1000 embryos/L and 2000 embryos/L), using 5 replicate individual culture tanks for each combined factor. The embryos were obtained by adding gametes to sea water, in a proportion 1 egg : 100 spermatozoids, and by discarding unfertilized floating eggs by decantation. Afterwards, the embryos were transferred to a culture system composed by cylindrical-conical plastic tanks of 2L. These were decontaminated and filled with 0.750L of sea water, continuously aerated through a sterile pipette of 3mL. These tanks were placed on metal shelves, artificially illuminated with daylight fluorescent lamps (18w/765, 400Lux) and maintained at 22°C. The larvae were fed each 2 days, with a mixture of microalgae Tetraselmis chuii, Phaeodactylum tricornumtum and Thalassiosira weliflogii at a concentration of 800-1000 microalgae/mL, adding 15µL, 50µL and 30µL to each individual tank, respectively for each of the initial larval densities introduced. There was an influence of the factor initial larval density in the mortality rate, wherein the number of larvae that died during the trial was much greater, the greater the initial density. There was also an influence of the factor induction of gametes release. The larvae obtained by the injection method with 0.125M KCl recorded a number of dead larvae slightly lower during the trial than the other methods. These results influenced the larval densities at the end of the trial. The factor initial larval density presented no influence, but the induction of gametal release did. At the end of the trial, the larval densities achieved through the injection method with 0.125M KCl were higher than those of other methods. Still, the densities of larvae that survived the trial were very low, under 16 larvae/L. During the 4 weeks trial, the larvae reached the post pluteus stage with 8 tri-radial spicules.